KR20060054397A - Process for preparing ethyleneamine - Google Patents

Abstract

The present invention relates to a process for the preparation of ethyleneamines, in particular diethylenetriamine (DETA), wherein the ethylenediamine (EDA) is continuously reacted in the presence of a heterogeneous catalyst and the reaction is carried out in a reaction column.

Description

Method for producing ethyleneamine {METHOD FOR PRODUCING ETHYLENE-AMINES}

The present invention provides a process for producing ethyleneamines, in particular diethylenetriamine (DETA), piperazine (PIP) and / or triethylenetetramine (TETA) by continuous reaction of ethylenediamine (EDA) in the presence of heterogeneous catalysts. It is about.

Ethyleneamines are used as solvents, stabilizers, or for the synthesis of chelating agents, synthetic resins, medicines, inhibitors, and surface-active substances.

In particular, diethylenetriamine (bis (2-aminoethyl) amine; DETA) is used as a solvent for dyes and for ion exchangers, pesticides, antioxidants, corrosion inhibitors, complexing agents, fiber aids and (acidic) gases. Starting material for the manufacture of absorbents.

Ethylenediamine (H ₂ N—CH ₂ —CH ₂ —NH ₂ ; EDA), which is required as starting material, may be prepared by known methods, for example by reaction of monoethanolamine (MEOA) with ammonia.

The literature describes a number of methods for producing ethyleneamines.

According to the prior art, ethyleneamines such as DETA are mostly in which the catalyst comprises, for example, nickel, cobalt, copper, precious metals such as Re, Ru, Rh, Pt, Pd, or combinations thereof as the active ingredient. Prepared from monoethanolamine (MEOA) and ammonia in a fixed bed reactor. The support material can be for example Al ₂ O ₃ , SiO ₂ or ZrO ₂ or a combination of these and other oxides. In order to maintain catalytic activity, in most cases it is necessary to introduce a small amount of hydrogen (eg about 0.001% by weight based on the amount of feed).

The main product generated during the process is EDA, and the byproducts generated are DETA, piperazine (PIP) and higher ethyleneamines, ie ethyleneamines having a higher boiling point than DETA (at the same pressure), and aminoethylethanolamine (AEEA). Other compounds.

Because of the relatively high market demand for DETA as well as the main product EDA, it is desirable to increase the selectivity of DETA over the selectivity obtained by simple routes in fixed bed reactors. The selectivity of EDA and DETA can be controlled within certain limits by the molar ratio of ammonia to MEOA. The high excess of ammonia forms EDA predominantly, especially at low MEOA conversions. Low ammonia excess and relatively high MEOA conversion increase the selectivity of DETA as well as other byproducts.

It is also possible to increase the DETA selectivity by returning part of the EDA to the reactor after concentration of the reaction product. However, this avoids the formation of other byproducts, especially AEEA.

EP-A2-197 611 (Union Carbide Corp.) describes a process for preparing polyalkylenepolyamines using two reactors connected in tandem.

In the first reactor, amination of MEOA with ammonia is carried out on a transition metal catalyst (Ni, Re on support).

The reaction product is also sent through a second reactor filled with a transition metal catalyst or a phosphate catalyst. In order to control the product distribution and to increase the selectivity for linear ethyleneamines, ethylenediamine derived from the workup of the reaction product of the second reactor and also comprising MEOA and H ₂ O is introduced before the second reactor.

A disadvantage of this method is that AEEA preferentially reacts further to produce piperazine, not DETA, and an additional amount of AEEA is formed as a result of the reaction of EDA and MEOA.

The synthesis of DETA can also be carried out by known methods by reacting EDA in a fixed bed reactor, where the by-products produced are mainly PIP (eg US Pat. No. 5,410,086 (Burgess), GB-A -1,508,460 (BASF AG) and WO-A1-03 / 010125 (Akzo Nobel).

For example, at a conversion of about 30%, a DETA selectivity of about 70% can be achieved. If pure EDA is used as starting material, AEEA will not form as a byproduct. Formation of higher ethyleneamines is greatly avoided by the partial conversion process.

However, due to the unfavorable position of chemical equilibrium, more PIP will be formed at higher conversions. In addition, due to the formation of ammonia during the conversion of EDA to DETA (2 EDA → DETA + NH ₃ ), the production of EDA by the reverse reaction of DETA and ammonia is also becoming increasingly important.

The partial conversion process leads to a high circulating stream (recycle) of the EDA, thus increasing the energy consumption, especially in the EDA purification column.

BASF's German patent application No. 10335991.5 (filed Aug. 1, 2003) discloses reacting monoethanolamine (MEOA) with ammonia in the presence of a catalyst in reactor 1, separating the resulting reaction product, and separating The obtained ethylenediamine (EDA) is reacted in the presence of a catalyst in a separate reactor (2) to give diethylenetriamine (DETA), where the resulting reaction product is sent to a separation process of the reaction product produced from reactor 1 And a method for producing ethyleneamine.

For the addition of alcohols to olepan to obtain the corresponding ethers [e.g. MTBE (methyl-tert-butyl ether) and TAME (tert-amyl methyl ether)], known processes carried out in reaction columns are described in the literature. It is described in. This process, also referred to as reactive distillation, is described in detail in, for example, the text "Reactive Distillation", edited by K. Sundmacher and A. Kienle, Verlag Wiley-VCH (2003).

Reactive distillation also applies in the field of esterification, saponification and transesterification, preparation and saponification of acetals, preparation of alkoxylates, aldol condensation, alkylation, hydrolysis of epoxides, hydration of olefins, isomerization and hydrogenation.

It is an object of the present invention to find an improved economical process for the selective production of ethyleneamines, including diethylenetriamine (DETA), in particular in high yield and space-time yield (STY).

[Spatial-time yields are in terms of 'product amount / (catalyst volume x time)' (kg / (L _catalyst xh)) and / or 'reactant amount / (reactor volume x time)' (kg / (L _reactor xh) Is given.]

The inventors have found that this object is achieved by a process for the preparation of ethyleneamine, which comprises continuously reacting ethylenediamine (EDA) in the presence of a heterogeneous catalyst and carrying out the reaction in a reaction column.

Ethyleneamines are in particular diethylenetriamine (DETA), piperazine (PIP) and / or triethylenetetramine (TETA).

Thereafter, the reaction proceeds according to the following scheme, for example.

2 EDA → DETA + NH ₃

2 EDA → PIP + 2 NH ₃

3 EDA → TETA + 2 NH ₃

DETA + EDA → TETA + NH ₃

According to the invention, it has been found that the synthesis of ethyleneamines, in particular DETA, by means of a continuous reaction (reactive distillation) in an EDA reaction column eliminates the prior art methods. Continuous stripping of DETA and / or TETA from the column below the reaction zone (through the bottom and / or side separators) can greatly suppress the secondary reactions, thus allowing the process to be carried out with a high conversion of EDA, even at full conversion. Can be.

By continuously removing ammonia from the column (preferably at the top of the column and also as a mixture with lower boiling components than DETA), the reverse reaction of DETA to EDA is greatly inhibited, thus accelerating the formation of DETA. Thus, the reaction may be carried out at other pressures, but may advantageously be carried out at a pressure lower than the optimum pressure range when using a conventional fixed bed reactor (tubular reactor with a catalyst fixed bed).

The absolute pressure of the column is preferably in the range> 0 to 20 bar, for example in the range 1 to 20 bar, in particular 5 to 10 bar.

The temperature of the section (reaction zone) of the column in which the reaction of EDA to ethyleneamine is carried out is preferably in the range from 100 to 200 ° C., in particular 140 to 160 ° C.

The theoretical number of plates in the column is preferably 5 to 100, more preferably 10 to 20, in total.

The number of theoretical plates in the reaction zone is preferably in the range from 1 to 30, in particular from 1 to 20, in particular from 1 to 10, for example 5 to 10.

The number of theoretical plates in the enrichment section above the reaction zone is preferably in the range from 0 to 30, in particular from 1 to 30, more in particular from 1 to 15, for example from 1 to 5.

The number of theoretical plates in the stripping section below the reaction zone is preferably in the range from 0 to 40, in particular from 5 to 30, in particular from 10 to 20.

The addition of EDA to the column can be carried out in liquid form or in gaseous form below the reaction zone.

The addition of EDA to the column can also be carried out in liquid form above the reaction zone.

In the process according to the invention, for example, pure EDA of purity> 98% by weight, in particular> 99% by weight, piperazine (PIP), for example> 0 to 25% by weight of PIP and / or other ethyleneamines Both EDAs may be fed into the column.

It is also possible to use EDA crude products from the reaction of MEOA with ammonia after partial or complete removal of ammonia and water.

The reaction is particularly preferably carried out in the presence of hydrogen, in particular in the presence of 0.0001 to 1% by weight, preferably 0.001 to 0.01% by weight of hydrogen, based on the amount of EDA supplied.

The addition of hydrogen to the column is preferably carried out under the reaction zone.

The mixture comprising ammonia, another boiling point (low boiling point component) lower than DETA (at the same pressure) and optionally hydrogen, is preferably removed through the top of the column.

The mixture removed through the top of the column may also contain a partial amount of unreacted EDA.

The mixture removed from the upper layer may also partially condense, during which the ammonia and optionally hydrogen are predominantly removed (evaporated) in gaseous form and the liquefied fraction may be fed to the column as reflux.

Here, the weight ratio of the amount of column reflux (column reflux) to the amount of feed of the column is preferably in the range from 0.1 to 30, particularly preferably from 0.5 to 10, in particular from 0.5 to 2.

The mixture of DETA, piperazine (PIP), TETA, and other ingredients (high boiling point components) having a higher boiling point than DETA (at the same pressure) is preferably removed through the bottom of the column.

The mixture removed through the bottom of the column may also include a partial amount of unreacted EDA or a total amount of unreacted EDA.

In one particular embodiment, the column below the reaction zone is further divided into side separations.

Unreacted EDA, PIP or mixtures thereof are preferably removed via lateral separation.

The product removed through the lateral separation may also include DETA.

The product produced through the side separation is removed in liquid form or in gaseous form.

In the reaction zone, the catalyst used is preferably a catalyst comprising Ni, Co, Cu, Ru, Re, Rh, Pd and / or Pt, shape-selective zeolite catalyst or phosphate catalyst.

Preferably the metal or metals of the transition metal catalyst, including Ru, Re, Rh, Pd and / or Pt, are preferably oxide based support materials (eg Al ₂ O ₃ , TiO ₂ , ZrO ₂ , SiO ₂ ) Or to a zeolite or activated carbon support material.

In a preferred embodiment, the catalyst used in the reaction zone is a catalyst comprising Pd and a zirconium dioxide support material.

The total content of metal of the supported transition metal catalyst preferably ranges from> 0% to 80% by weight, in particular from 0.1% to 70% by weight, more particularly from 5% to 60% by weight, more particularly from 10% to 50%. Weight percent, where all percents are based on the weight of the support material.

In the case of supported noble metal catalysts which are preferred catalysts, the total content of the noble metal is in particular> 10% to 20% by weight, in particular 0.1% to 10% by weight, very particularly 0.2% to 5% by weight, more particularly 0.3% to 2 weight percent, where all percents are based on the weight of the support material.

The heterogeneous catalyst may be deposited in the form of a fixed catalyst bed in the column or in a separate vessel outside the column. It can also be used as a loose bed, for example as a glass layer in a distillation packing, can be molded to form a dumped packing or molding, for example pressed to a Raschig ring. Can be obtained, incorporated into the filtration fabric and shaped to obtain a bale or column packing, applied to the distillation packing (coating) or used in the form of a suspension in the column, preferably suspended on a column tray. Use in the form of water.

In methods using heterogeneously catalyzed reactive distillation, the bale technology developed by CDTech can be advantageously used.

A further technique is the construction of special trays with packed or suspended catalysts.

Multi-channel packing or exchange channel packing (see eg WO-A-03 / 047747) allows the introduction of catalysts in particulate form (eg spherical, pelletized, tableted) simply by lowering the mechanical stress of the catalyst and Can be removed.

An important point of reactive distillation is the provision of the residence time required for the reaction process. It is necessary to increase the residence time of the liquid in the column in a targeted manner compared to non-reactive distillation. Special designs inside the column are used, for example tray columns with bubble cap trays with significantly increased fill levels, long residence times of material descending to the tray column, and / or externally aligned external time-delay vessels. Closed packing offers the possibility to increase the residence time of the liquid approximately three times compared to the column packed dumped or ordered packing.

The design of the reaction column (column section, enrichment section, stripping section and number of plates in the reaction zone, reflux ratio, etc.) can be adopted according to methods familiar to those skilled in the art.

Reaction columns are described, for example, in the literature.

WO-A-97 / 16243 (May 9, 1997),

DD-Patent 100701 (October 5, 1973),

U.S. Patent 4,267,396 (May 12, 1981),

및 그에 인용된 참고문헌,

And references cited therein,

DE-C2-27 14 590 (August 16, 1984),

EP-B-40724 (May 25, 1983),

EP-B-40723 (July 6, 1983),

DE-C1-37 01 268 (14 April 1988),

DE-C1-34 13 212 (September 12, 1985),

EP-B1-461 855 (August 9, 1995),

EP-B1-402 019 (June 28, 1995),

WO-A1-03 / 047747 (Basj AG, June 12, 2003), and

WO-A1-97 / 35834.

In a preferred embodiment, the process of the invention is carried out in a column for carrying out reactive distillation of heterogeneous particulate catalysts with ordered packing or random packing to form an intermediate space inside the column, as described in WO-A1-03 / 047747. Carried out in the presence, wherein the column has first and second subregions, which are alternately arranged and differ in the specific surface area of the ordered packing or random packing, in which the gas passes through the ordered packing or random packing The ratio of the running diameter for the stream to the equivalent diameter of the catalyst particles is in the range of 2 to 20, preferably in the range of 5 to 10, wherein the catalyst particles are introduced into the intermediate space and are loosely distributed and discharged under the action of gravity, the second partial region Has a ratio of the flow diameter for the gas stream through ordered packing or random packing to the equivalent diameter of the catalyst particles of less than 1, The catalyst particles are not introduced into the second partial region. Preferably, for gas and / or liquid dropping, the column is operated in such a way that the release limit dropping amount reaches at most 50% to 95%, preferably 70% to 80%. See claims 9 and 10 of the above patent application.

The work-up of the product stream produced in the process according to the invention, which mainly comprises the desired DETA, but also comprises triethylenetetramine (TETA), PIP and unreacted EDA, is carried out according to distillation methods known to those skilled in the art. (See, eg, PET Report No. 138 ("Alkyl Amines", SRI International, 03/1981, pages 81-99, 117).

The distillation columns required for the distillative isolation of the individual pure products, mainly the desired DETA, can be designed using methods familiar to those skilled in the art (for example, number of plates, reflux ratio, etc.).

The method using the side separators in the stripping section below the reaction zone of the reaction column provides certain advantages during further workup for the isolation of the individual pure products.

The side separation stream, which consists predominantly of PIP, unreacted EDA or mixtures thereof, comprises only a small amount of DETA and high boiling components, especially when the side separation stream is removed in the gas phase. Thus, instead of being sent first to the removal of low boiling components from the DETA and high boiling components, it can be fed directly into the aftertreatment section in which purification of EDA and PIP is carried out, separate from the bottom separation stream of the reaction column.

The partial amount of side stream can also be returned to the reaction column itself. This is particularly advantageous if the side stream mainly contains EDA and little or no PIP.

Since the bottoms split stream of the reaction column in this method contains smaller amounts of low boiling components (EDA and PIP), it relieves the column pressure to remove low boiling components from DETA and high boiling components.

If reactive distillation is carried out at low pressure, for example 1 to 3 bar, it is also possible to obtain a bottoms split stream at a bottom temperature of about 200 to 240 ° C. without EDA and PIP. The bottom separator stream may then be sent to a post-treatment section, where purification of the DETA is optionally performed, instead of first being sent to the separation of the low boiling component from the DETA and the high boiling component.

Using the method of the present invention, DETA can be selected to have a selectivity of> 18%, in particular> 20%, more particularly> 22% (wherein all% is based on EDA) and> 30%, especially> 40%, more particularly> 50% Can be generated with an EDA conversion rate of.

Example A

1 of Attachment 1 shows that pure EDA or EDA / PIP mixtures are continuously fed with hydrogen to the reaction column under catalyst packing, and the DETA, unreacted EDA, PIP, TETA and high boiling point components (SS, ie, boiling point than DETA) A mixture comprising a high component) represents one form of the process according to the invention, obtained through the bottom. Ammonia, hydrogen and low boiling point components (LS, ie lower boiling point than DETA) are separated in the upper layer.

Example B

FIG. 2 of Attachment 2 shows that a pure EDA or EDA / PIP mixture is continuously sent to the reaction column under catalyst packing with hydrogen and includes DETA, TETA and high boiling components (SS, ie components having higher boiling points than DETA). One form of the process according to the invention is obtained in which the mixture is obtained through the bottom. Ammonia, hydrogen and low boiling point components (LS, ie lower boiling point than DETA) are separated in the upper layer.

At the side separation in the stripping section below the reaction zone of the reaction column, the PIP, optionally as a mixture with EDA, is separated.

Examples 1-4

The catalyst was prepared using a zirconium dioxide extrudate of 3.2 mm in diameter and 1 to 2 cm in length.

2700 g of the support was impregnated with 770.0 mL of an aqueous palladium nitrate solution (92% H ₂ O absorption rate) to produce a palladium having a 0.9% by weight palladium loading calculation. Impregnation was performed repeatedly. It was dried for 6 hours at 120 ° C. (1 hour to heat to 120 ° C.) in a drying cabinet and calcined at 450 ° C. (2 hours to heat to 450 ° C.) for 2 hours in a covered furnace.

The reactions of Examples 1 to 4 were all carried out at 5 bar absolute. Hydrogen was fed into the column under the catalyst bed at a rate of 6 L / h.

Examples 1 and 2 were carried out after filling 755 g of the prepared catalyst into an experimental column 55 mm in diameter containing an ordered packing as recited in claim 9 of patent application WO-A1-03 // 047747 and related descriptions. It was.

The theoretical number of plates under the catalyst bed was six. The catalyst packing has 3.5 theoretical plates. The theoretical number of plates on the catalyst bed was one.

Example # 1

Liquid EDA was fed at a rate of 400 g / h over the catalyst bed at room temperature. Reflux was set to 800 g / h. The criteria for the column temperature in the stable-step operation was 186 ° C.

The bottom product of the column has a composition (in weight percent) of 65% EDA, 9.7% DETA and 16% piperazine. The other component was a high boiling point component.

This corresponded to 25% DETA selectivity and 41% EDA conversion.

Example 2

Liquid EDA was fed at a rate of 400 g / h under the catalyst bed at room temperature. Reflux was set to 400 g / h. The criterion of the column temperature in stable-step operation was 183 ° C.

The bottom product of the column has a composition (in weight percent) of 74.6% EDA, 6.1% DETA and 13.2% piperazine. The other component was a high boiling point component.

This corresponded to a DETA selectivity of 21.7% and an EDA conversion of 30.6%.

Example # 3 was carried out after filling 934 g of the prepared catalyst into an experimental column 55 mm in diameter containing an ordered packing as recited in claim 9 of patent application WO-A1-03 // 047747 and the related description.

The theoretical number of plates under the catalyst bed was 15. The catalyst packing has ten theoretical plates. The theoretical number of plates on the catalyst bed was 10.

Example 3

Liquid EDA was fed at a rate of 100 g / h over the catalyst bed at room temperature. Reflux was set to 800 g / h. The criterion of the column temperature in the stable-step operation was 162 ° C.

The bottom product of the column has a composition (by weight percent) of 55% EDA, 12% DETA and 21% piperazine. The other component was a high boiling point component.

This corresponded to a 21% DETA selectivity and 55% EDA conversion.

Claims (34)

A process for producing ethyleneamine, comprising continuously reacting ethylenediamine (EDA) in the presence of a heterogeneous catalyst and carrying out the reaction in a reaction column. The process for producing ethyleneamine according to claim 1, wherein the ethyleneamine is diethylenetriamine (DETA), piperazine (PIP) and / or triethylenetetramine (TETA). The method according to claim 1 or 2, wherein the absolute pressure in the column is in the range of> 0 to 20 bar. The process according to any one of claims 1 to 3, wherein the temperature of the section (reaction zone) of the column in which the reaction of EDA to ethyleneamine is carried out is in the range of 100 to 200 ° C. The method according to any one of claims 1 to 4, wherein the number of theoretical plates in the column ranges from 5 to 100 in total. The method according to claim 1, wherein the number of theoretical plates in the reaction zone ranges from 1 to 30. 7. The method according to claim 1, wherein the number of theoretical plates in the enrichment section above the reaction zone is in the range of 0 to 30. 8. The method according to claim 1, wherein the number of theoretical plates in the stripping section below the reaction zone ranges from 0 to 40. 9. 9. The catalyst according to claim 1, wherein the catalyst used in the reaction zone comprises Ni, Co, Cu, Ru, Re, Rh, Pd and / or Pt, or shape-selective zeolite catalyst or phosphate catalyst. A method comprising a catalyst. The process according to claim 1, wherein the catalyst used in the reaction zone is a catalyst comprising Pd and a zirconium dioxide support material. The process according to claim 1, wherein the catalyst is introduced into a reaction column in the form of a loose bed. The process according to claim 1, wherein the catalyst is introduced into a distillation packing in the form of a glass bed. The process according to claim 1, wherein the catalyst is in the form of a coating on the distillation packing. The process of claim 1, wherein the catalyst is in a retention vessel located above the column. The process according to claim 1, wherein the addition of EDA to the column is carried out in liquid form below the reaction zone. The process according to claim 1, wherein the addition of EDA to the column is carried out in gaseous form below the reaction zone. The process according to claim 1, wherein the addition of EDA to the column is carried out in liquid form above the reaction zone. 18. The method of any one of claims 1 to 17, wherein EDA having a purity> 98% by weight is sent to the column. The method according to claim 1, wherein the column comprises EDA, piperazine (PIP) and / or other ethyleneamines introduced. 20. The process according to any one of claims 1 to 19, wherein the reaction is carried out in the presence of hydrogen. The process according to claim 1, wherein the reaction is carried out in the presence of 0.0001 to 1% by weight of hydrogen, based on the amount of EDA supplied. 22. The process of claim 20 or 21, wherein the addition of hydrogen to the column is carried out below the reaction zone. 23. The process according to any one of the preceding claims, wherein a mixture of ammonia, another boiling point lower than DETA (low boiling point component) and optionally a mixture of hydrogen is removed through the top of the column. 24. The method of any one of claims 1 to 23, wherein the mixture removed from the top of the column also comprises unreacted EDA. The process according to claim 23 or 24, wherein the mixture removed from the upper layer is partially condensed, during which ammonia and optionally hydrogen are removed predominantly in gaseous form, and the liquefied fraction is fed to the column as reflux. How to be. 26. The process of any one of claims 1 to 25 wherein the weight ratio of the amount of reflux in the column to the amount of feed to the column is from 0.1 to 30. 27. The method according to any one of claims 1 to 26, wherein DETA, piperazine (PIP), TETA, and other components with higher boiling points than DETA (high boiling point components) are removed by the bottom of the column. The method of claim 1, wherein the mixture removed by the bottom of the column also comprises a partial amount of unreacted EDA or a total amount of unreacted EDA. 29. The method of any one of claims 1 to 28, wherein the column below the reaction zone is divided by lateral separators. The method of claim 1, wherein the unreacted EDA, PIP, or mixtures thereof are removed via side separations. 31. The method of any one of claims 1-30, wherein the product removed through the lateral separator comprises DETA. 32. The method of any one of the preceding claims, wherein the product produced through the side separation is removed in liquid form. 32. The method of any one of claims 29-31, wherein the product produced through the side separation is removed in gaseous form. 34. The method of any one of claims 1 to 33, wherein the DETA is produced with a selectivity of> 20% and an EDA conversion of> 30% based on the EDA.

Images